A Treatise on Universal Algebra, With Applications
(engl.)
at The Cornell Library Historical Mathematics Monographs
[historical.library.cornell.edu/cgi-bin/cul.math/docviewer?did=01950001&seq=5]

Religion in the Making
(engl.)
at Theology
[theology.co.kr/whitehead/religion/]

The Concept of Nature
(engl.)
at Brock University
[www.brocku.ca/MeadProject/Whitehead/Whitehead_1920/White1_pref.html]